IEEE C802.16n-11/0167r2 Project IEEE 802.16 Broadband Wireless Access Working Group <http://ieee802.org/16> Title HR-MS Direct Communication Link Setup Date Submitted 2011-09-12 Source(s) Haiguang Wang, Hoang Anh Tuan, Jaya Shankar, Shoukang Zheng, Yeow Wai Leong, Joseph Teo Chee Ming Voice: +65 6408-2256 E-mail: hwang@i2r.a-star.edu.sg Institute for Infocomm Research 1 Fusionopolis Way, #21-01, Connexis (South Tower) Singapore 138632 Re: Call for contributions for 802.16n AWD Abstract In this proposal, we proposed a procedure for HR-networks in setting up HR-MS direct communication in HR-BS or HR-RS appears in the network. Purpose To discuss and adopt the proposed text in the 802.16n draft Text Notice Copyright Policy Patent Policy This document does not represent the agreed views of the IEEE 802.16 Working Group or any of its subgroups. It represents only the views of the participants listed in the “Source(s)” field above. It is offered as a basis for discussion. It is not binding on the contributor(s), who reserve(s) the right to add, amend or withdraw material contained herein. The contributor is familiar with the IEEE-SA Copyright Policy <http://standards.ieee.org/IPR/copyrightpolicy.html>. The contributor is familiar with the IEEE-SA Patent Policy and Procedures: <http://standards.ieee.org/guides/bylaws/sect6-7.html#6> and <http://standards.ieee.org/guides/opman/sect6.html#6.3>. Further information is located at <http://standards.ieee.org/board/pat/pat-material.html> and <http://standards.ieee.org/board/pat>. HR-MS Direct Communication Link Setup Haiguang Wang, Hoang Anh Tuan, Jaya Shankar, Shoukang Zheng, Yeow Wai Leong, Joseph Teo Chee Ming Institute for Infocomm Research (I2R) 1 Fusionopolis Way, #21-01, Connexis South Tower Singapore 138632 1. Introduction 1 IEEE C802.16n-11/0167r2 2. Summary 3. Text Proposal for IEEE 802.16n AWD Note: The text in BLACK color: the existing text in AWD The text in RED color: the removal of existing AWD text The text in BLUE color: the new text added to the Multi-Carrier DG Text [-------------------------------------------------Start of Text Proposal---------------------------------------------------] [Adopt the following text in the 802.16n Document (XXX --- document number)] {Remedy 1: Modify 17.2.2.4 and 17.3.2.4 as indicated} 17.2.2.4 HR-MS Direct Communication with Infrastructure Stations HR-BS/HR-RS shall check DSA_REQ messages received from HR-MS and determine whether HR-MS direct communication can be adopted for a flow. The HR-BS/HR-RS may help the source and destination HR-MSs setting up a direct communication link through DSA signaling. HR-BS knows the possibility of setting up a direct communication between two HR-MSs by checking the HRMS neighbor tables. If the two nodes are neighbor, HR-MS may schedule the two HR-MSs to do channel measurement and determine whether a direct communication link should be setup. Before a service flow can be conveyed over the link between source and destination HR-MSs To support direct communication between a pair of HR-MSs, a direct communication link shall be setup between the HRMSs first if it has not been setup yet., The a CID. When the link is first setup, two basic CIDs are assigned to each DC-link to facilitate the two way communication for control message. Of the two assigned, each HR-MS is assigned one of the CIDs for transmitting the control message such as ARQ. The CID is referred in the link management messages such as link deletion and status report. A direct communication link is a link between a pair of HR-MS. It is identified by a CID. A security association may be setup between the two HR-MS linked by the direct communication. HR-BS manages the link by referring to the CID assigned to this link. The procedure to setup security association over a direct communication link is defined in section 17.2.10.1.1. The security association is shared by different flows over the direct communication link. After a direct communication link is setup, data flows can be setup over the DC-link with the DSA transactions as specified in section 17.2.2.5. When a flow is assigned over a DC-link, the sender and receiver shall monitor on the CIDs within the MAP and transmit/receive over the allocated resources. There are a few steps to setup a direct communication link between two HR-MS. The first step is that the two HR-MS need to do a channel measurement. After the channel measurement, the two HR-MSs shall 2 IEEE C802.16n-11/0167r2 report the measurement results to the HR-BS and HR-BS shall make a decision whether it will setup a direct communication link between the two HR-MSs. If HR-BS decides to setup a direct communication link, it shall assign a CID to the target link. After that, it may help the two sides setup a security association between the two HR-MSs. Once a security association is setup, then the communication link is considered being established between the two HR-MSs and service flows can be carried on the link. Figure 1 shows the procedure to setup a direct communication link between HR-MSs. HR-BS may take a few steps to setup a direct communication link between two HR-MS. Firstly, the HR-BS shall schedule the two HR-MSs do a channel measurement with the method specified in section 17.2.2.3. The HR-MSs reports the channel measurement results to the HR-BS after the measurement. If HR-BS decides to setup a direct communication link, it shall assign CIDs to the direct communication link and send CIDs to the two HR-MSs using DC-LINK-CREATION-REQ messages. The HR-MSs shall sends back DC-LINK-CREATION-ACK for confirmation. After receiving DC-LINK-CREATION-ACK from both HR-MSs, the HR-BS may help the two HR-MSs establish a security association over the direct communication link if security is required. The setup of security association over direct communication link is specified in section 17.2.10. Once a security association is setup, then the communication link is considered being established between the two HR-MSs. The HR-MSs shall find the existing flows between the two HR-MSs and move the existing flows by setting up new flows over the direct communication link with DSA method specified in section 17.2.2.5. Figure 801shows the procedure to setup a direct communication link between HR-MSs. When HR-MS want to delete the direct communication link, it shall send DC-LINK-DELETE-REQ to the two HR-MSs involved. 3 IEEE C802.16n-11/0167r2 Start Start the process of setting up direct communication link Schedule channel measurement between source and destination HR-MS (using ranging code) and process the channel measurement report from HR-MSs after receiving the measurement report No Should Direct Communication link be setup? Yes Create direct communication link Setup Security Association Move the existing flow to DC link with DSC transaction Finish Figure 1— The overall procedure to setup direct communication 17.2.2.4.1 Direct Communication Management 17.2.2.4.1.1 Direct Communication Link Creation When HR-BS creates direct communication link between two HR-MSs. It shall allocate a CID for the direct communication link and send link creation message to both source and destination HR-MSs. Direct communication link creation can only be initiated by the HR-BS. Table 1— Direct Communication Link Creation Request Syntax DC-LINK-CREATE-REQ () { Management Message Type = [TBD] CID of source HR-MS CID of destination HR-MS CID assigned for transmitting DC link CID assigned for receiving } Size (bit) Notes 8 — 16 16 16 16 CID assigned for transmitting 4 IEEE C802.16n-11/0167r2 The CID is used by the HR-MS for transmitting. The peer HR-MS of the DC-link shall receive on the resource specified by this CID. CID assigned for receiving The HR-MS shall receive on the resource specified by this CID since it is assigned to the peer HR-MS on the DC-Link for transmission. The HR-MSs shall send back a response once they receive the direct communication link creation request. Table 2— Direct Communication Link Creation Response Syntax DC-LINK-CREATE-ACK RSP() { Management Message Type = [TBD] CID of DC link Confirmation Code Reserved Size (bit) Notes 8 16 41 — CID assigned for transmission 0x00: accept 0x01: reject 0x02 – 0x0f: reserved — 47 } Once the HR-BS receives responses from both HR-MSs, it can continue on other steps of direct communication setup. 17.2.2.4.1.2 Direct Communication Link Deletion When HR-BS wants remove a direct communication link, it shall send deletion request to both HR-MS and wait for responses from the HR-MSs. Table 3-- Direct Communication Deletion Request Syntax DC-LINK-DEL () { Management Message Type = [TBD] CID of DC link } Size (bit) Notes 8 16 — CID assigned for transmitting The HR-MS shall reply with reasons to HR-BS when it receives the link deletion request from HR-BS. Table 4—Direct Communication Deletion Response Syntax Size (bit) Notes DC-LINK-DEL-ACK () { 5 IEEE C802.16n-11/0167r2 Management Message Type = [TBD] CID of DC link Confirmation Code 8 16 41 Reserved 47 — CID assigned for transmitting 0x00: accept 0x01: reject 0x02 – 0x0f: reserved — } 17.2.2.4.1.3 Direct Communication Link Report HR-BS may require the HR-MS report the status of the direct communication link by sending a request to the relative HR-MS. Table 5—Direct Communication Link Report Request Syntax Size (bit) DC-LINK-REPORT-REQ () { Management Message Type = [TBD] CID of DC link Report Request TLVs } Notes 8 — 16 CID assigned for transmitting variable Specified in section 11.11 Report Request TLVs The HR-MS only provides measurement for CINR and RSSI. HR-MS shall send back report regarding the direct communication link when it receives a link report request from HR-BS. Table 6—Direct Communication Link Report Syntax DC-LINK-REPORT-REQRSP () { Management Message Type = [TBD] CID of DC link Link state reserved Report Response TLVs Size (bit) Notes 8 16 31 — CID assigned for transmitting 0x00: active 0x01: no link found 0x02 – 0x07: reserved — 57 variable Specified in section 11.11 } Upon sending a Channel Measurement REP-RSP message, an SS shall reset all its measurement counters for each channel on which it reported. 6 IEEE C802.16n-11/0167r2 17.3.2.4 HR-MS Direct Communication with Infrastructure Stations HR-BS/HR-RS shall check DSA_REQ messages received from HR-MS and determine whether HR-MS direct communication can be adopted for a flow. The HR-BS/HR-RS may help the source and destination HR-MSs setting up a direct communication link through DSA signaling. HR-BS knows the possibility of setting up a direct communication between two HR-MSs by checking the HRMS neighbor tables. If the two nodes are neighbor, HR-MS may schedule the two HR-MSs to do channel measurement and determine whether a direct communication link should be setup. Before a service flow can be conveyed over the link between source and destination HR-MSs To support direct communication between a pair of HR-MSs, a direct communication link shall be setup between the HRMSs first if it has not been setup yet., The a CID. When the link is first setup, two STIDs are assigned to each DC-link to facilitate the two way communication. Each HR-MS is assigned one STID for identifying it as the transmitter over the DC-link The Assignment A-MAP IE for direct communication link is CRC masked as specified in Table 849. The STID is referred in the link management messages such as link deletion and status report. A direct communication link is a link between a pair of HR-MS. It is identified by a STID. A security association may be setup between the two HR-MS linked by the direct communication. HR-BS manages the link by referring to the STID assigned to this link. The procedure for setup security association over a direct communication link is defined in section 17.3.10.1.1. The security association is shared by different flows over the direct communication link. After a direct communication link is setup, flows can be setup over the direct communication link with the DSA transactions as specified in section 17.3.2.5. When a flow is assigned over a direct communication link, the sender and receiver shall monitor on direct communication related STIDs within the MAP and transmit/receive over the allocated resources. There are a few steps to setup a direct communication link between two HR-MS. The first step is that the two HR-MS need to do a channel measurement. After the channel measurement, the two HR-MSs shall report the measurement results to the HR-BS and HR-BS shall make a decision whether it will setup a direct communication link between the two HR-MSs. If HR-BS decides to setup a direct communication link, it shall assign a STID to the target link. After that, it may help the two sides setup a security association between the two HR-MSs. Once a security association is setup, then the communication link is considered being established between the two HR-MSs and service flows can be carried on the link. Figure 2 shows the procedure. HR-BS may take a few steps to setup a direct communication link between two HR-MS. Firstly, the HR-BS shall schedule the two HR-MSs do a channel measurement with the method specified in section 17.3.2.3. The HR-MSs reports the channel measurement results to the HR-BS after the measurement. If HR-BS decides to setup a direct communication link, it shall assign STIDs to the direct communication link 7 IEEE C802.16n-11/0167r2 and send CIDs to the two HR-MSs using DC-LINK-CREATION-REQ messages. The HR-MSs shall sends back AAI-DC-LINK-CREATION-ACK for confirmation. After receiving AAI-DC-LINK-CREATION-ACK from both HR-MSs, the HR-BS may help the two HR-MSs establish a security association over the direct communication link if security is required. The setup of security association over direct communication link is specified in section 17.3.10. Once a security association is setup, then the communication link is considered being established between the two HR-MSs. The HR-MSs shall find the existing flows between the two HR-MSs and move the existing flows by setting up new flows over the direct communication link with DSA method specified in section 17.3.2.5. Figure 902 shows the procedure to setup a direct communication link between HR-MSs. When HR-MS want to delete the direct communication link, it shall send AAI-DC-LINK-DELETE-REQ to the two HR-MSs involved. Start Start the process of setting up direct communication link Schedule channel measurement between source and destination HR-MS (using ranging code) and process the channel measurement report from HR-MSs after receiving the measurement report Should Direct Communication link be setup? No Yes Create direct communication link Setup Security Association Move the existing flow to DC link with AAI-DSC transaction Finish Figure 2—The overall procedure to setup direct communication 17.3.2.4.1 Direct Communication Link Management 17.3.2.4.1.1 Direct Communication Link Creation 8 IEEE C802.16n-11/0167r2 When HR-BS creates direct communication link between two HR-MSs. It shall send link creation message to both source and destination HR-MSs. Direct communication link creation can only be initiated by the HR-BS. Table 7—Direct Communication Link Creation Request Syntax AAI-DC-LINK-CREATE-REQ () { FID Type STID of source/destination HR-MS STID for transmitting STID for receiving } Size (bit) Notes 4 5 12 12 12 — STID assigned to DC link STID assigned to DC link STID for transmitting The STID is used by the HR-MS for transmitting. The peer HR-MS of the DC-link shall receive on the resource scheduled with this STID. STID for receiving The HR-MS shall receive on the resource assigned to this STID since it is assigned to the peer HR-MS on the DC-Link for transmission. The HR-MSs shall send back a response once they receive the direct communication link creation request. Table 8—Direct Communication Link Creation Response Syntax AAI-DC-LINK-CREATE-ACK () { FID Type STID for transmitting Confirmation Code Reserved Size (bit) Notes 4 5 12 1 — 47 STID assigned to DC link 0x00: accept 0x01: reject 0x02 – 0x0f: reserved — } Once the HR-BS receives responses from both HR-MSs, it can continue on other steps of direct communication setup. 17.3.2.4.1.2 Direct Communication Link Deletion When HR-BS wants remove a direct communication link, it shall send deletion request to both HR-MS and wait 9 IEEE C802.16n-11/0167r2 for responses from the HR-MSs. Table 9—Direct Communication Deletion Request Syntax Size Notes (bit) AAI-DC-LINK-DEL () { FID 4 — Type 5 STID for transmitting 12 STID assigned to DC link } The HR-MS shall reply with reasons to HR-BS when it receives the link deletion request from HR-BS. Table 10—Direct Communication Deletion Response Syntax AAI-DC-LINK-DEL-ACK () { FID Type STID for transmitting Confirmation Code Reserved Size (bit) Notes 4 5 12 41 — 47 STID assigned to DC link 0x00: accept 0x01: reject 0x02 – 0x0f: reserved — } 17.3.2.4.1.3 Direct Communication Link Report HR-BS may require the HR-MS report the status of the direct communication link by sending a request to the relative HR-MS. Table 11—Direct Communication Link Report Request Syntax AAI-DC-LINK-REPORT-REQ () { FID Type STID for transmittting } Size (bit) Notes 8 5 12 — STID assigned to DC link HR-MS shall send back report regarding the direct communication link when it receives a link report request from HR-BS. 1 0 IEEE C802.16n-11/0167r2 Table 12—Direct Communication Link Report Syntax AAI-DC-LINK-REPORT-REQ () { FID Type STID for transmitting Link state reserved Size (bit) Notes 4 5 12 31 — 57 STID assigned to DC link 0x00: active 0x01: no link found 0x02 – 0x07: reserved — } {Remedy 2: Modify Table 849 in 16.3.5.5.2.4 as indicated} CRC Mask A 16-bit CRC is generated based on the randomized contents of assignment A-MAP IE and is masked by 16-bit CRC mask using the bitwise XOR operation. The 16-bit masked CRC is constructed using a 1 bit masking prefix, a 3 bit message type indicator, and 12 bit Masking Code as described in Table 849. Table 849 – Description of CRC Mask Masking Prefix (1 bit MSB) 0b0 Remaining 15 bit LSBs Type Indicator 0b000 0b001 0b010 0b011 0b1 Masking Code 12 bit STID or TSTID Refer to Table 850 Refer to Table 851 12 bit STID for direct communications 15 bit RA-ID: The RA-ID is derived from the AMS' random access attributes (i.e., superframe number (LSB 5bits), frame_index (2 bits), preamble code index for ranging or BR (6 bits) and opportunity index for ranging or BR (2 bits)) as defined below: RA-ID = (LSB 5bits of superframe number | frame_index | preamble_code_index | opportunity_index) {Remedy 3: Insert the following new section into 17.2.2} 17.2.2.x.y Support for direct multicast operation 1 1 IEEE C802.16n-11/0167r2 Two-way direct multicast among a group of HR-MS is supported through the following addressing mechanism: - The base station assigns a 16-bit CID to each HR-MS of a two-way direct communications group. The CIDs assigned to different HR-MSs belonging to the same group can be the same or different; - The base station can also specify one primary management CID for itself to multicast to all HR-MSs belonging to a particular two-way direct communication group; - The base station informs all members of each two-way direct communication group of all the CIDs that have been assigned to the members of the group; including the CID reserved by the base station, if such a CID is reserved. - For each DL-MAP Information Element, or UL-MAP Information Element, the base station specified the CID of the allocated HR-MS. {Remedy 4: Insert the following new section into 17.3.2} 17.3.2.x.y Support for direct multicast operation Two-way direct multicast among a group of HR-MS is supported through the following addressing mechanism: - The base station assigns a 12-bit Two-Way Direct Multicast (TWDM) address to each HR-MS of a twoway direct communication group; each assigned TWDM address includes two non-overlapping fields, i.e., Two-way Group Identifier (TGID) and Two-way Transmitter Identifier (TTID). All HR-MSs belonging to the same two-way direct communication group share the same TGID. The TTID of the HRMSs belonging to the same group can be the same or different. - For each two-way direct communication group, the base station can reserve one value of TTID for itself. The base station uses the reserved TTID to transmit data/control messages to the HR-MS belonging to the two-way direct communication group; - The base station informs all members of each two-way direct communication group of all the values of TTIDs that have been assigned to the member of the group; including the TTID reserved by the base station, if such a TTID is reserved. - For each broadcasted Assignment A-MAP IE, the base station employs the CRC mask corresponding to Type Indicator = 0b011, as specified in Table 849. The 12 bit TWDM of the transmitting station is used in the place of STID. [-------------------------------------------------End of Text Proposal----------------------------------------------------] References [1] IEEE 802.16n-10/0048, “802.16n System Requirements Document including SARM annex”, January 2011. [2] IEEE 802.16n-10/0049, “802.16n Table of Contents for Amendment Working Draft”, January 2011. 1 2